Dwane Casey has coached the Toronto Raptors to be consistent contenders in the Eastern Conference. AP

DWANE Casey spent five years turning the Toronto Raptors into a contender in the Eastern Conference.

After the most successful season in franchise history, the Raptors moved quickly to make sure he sticks around to continue the work.

Casey and the Raptors agreed on Thursday (Friday, Manila time) to a three-year, $18 million contract extension, a person with knowledge of the situation told The Associated Press. The person spoke on condition of anonymity because the team has not announced the deal.

Casey was under contract for one more season, but the new terms will kick in starting with next season.

Raptors GM Masai Ujiri promised last week that the deal would get done "in his sleep," and he worked quickly to make it happen.

Casey inherited a team that went 22-60 in 2010-11 and had long suffered from a stigma of playoff failures. He methodically molded the Raptors into a hard-nosed, defensive-minded team that won a franchise-record 48 games in his third season and has improved upon that number in each of the last two years, culminating in a 56-26 record this season.

He entered the season still feeling some pressure after back-to-back first-round exits. But the Raptors beat the Pacers and the Heat in seven-game series and handed the Cleveland Cavaliers their first two losses of the playoffs in a six-game defeat in the Eastern Conference finals.

"I really think we're a step ahead in the process," Casey said after the Game 6 loss to Cleveland. "The players worked and put themselves in this process. We're still a relatively young team to talk about competing for a championship, but they put themselves in that position by hard work and fighting through things this season."

Along the way, the well-respected Casey has displayed a strong ability to develop talent. He helped the mercurial Kyle Lowry harness his attitude and aggression and blossom into one of the best point guards in the league, helped DeMar DeRozan diversify his game and become one of the better mid-range scorers in the league and, most recently, got Bismack Biyombo to realize his potential after struggling in Charlotte.

Now Lowry and DeRozan are All-Stars and Biyombo has positioned himself for a massive pay day in free agency.

"We still have a ways to go, and I've said this the whole time, that next step is probably the biggest step we have to take as an organization and as individuals," Casey said. "Myself included, the coaching staff, each player. We just talked in there a while ago about what each guy has to do, what they have to bring back to the table for us to take the next step, that next step, and it's not going to be easy."